We studied how older people describe others with cognitive impairment. Forty-two focus groups represented African Americans, American Indians, Chinese Americans, Latinos, Vietnamese Americans, and Whites other than Latinos (Whites) (N = 396, ages 50+), in nine locations in the United States of America. Axial coding connected categories and identified themes. The constant comparison method compared themes across ethnic groups. African Americans, American Indians and Whites emphasised memory loss. African Americans, American Indians, Latinos and Whites stressed withdrawal, isolation and repetitive speech. African Americans, American Indians, Vietnamese Americans and Whites emphasised ‘slow thinking’. Only Whites described mood swings and personality changes. Many participants attributed dementia to stress. Terms describing others with dementia included ‘Alzheimer's’, ‘dementia’, ‘senile’ and ‘crazy’. Euphemisms were common (‘senior moment’, ‘old timer's disease’). Responses focused on memory, with limited mention of other cognitive functions. Differences among ethnic groups in descriptions of cognitive health and cognitive impairment underscore the need to tailor public health messages about cognitive health to ways that people construe its loss, and to their interest in maintaining it, so that messages and terms used are familiar, understandable and relevant to the groups for which they are designed. Health promotion efforts should develop ethnically sensitive ways to address the widely held misperception that even serious cognitive impairment is a normal characteristic of ageing and also to address stigma associated with cognitive impairment.